List of practice Questions

In pteridophytes, main plant body is a , which is into true roots, stem and leaves. Fill the blanks in above statement and select the correct option.
If a circle of radius $R$ passes through the origin $O$ and intersects the coordinate axes at $A$ and $B$, then the locus of the foot of perpendicular from $O$ on $AB$ is :
If the angle of intersection at a point where the two circles with radii 5 cm and 12 cm intersect is $90^{\circ}$, then the length (in cm) of their common chord is :
If a circle $C$ passing through the point $(4,0)$ touches the circle $x^2 + y^2 + 4x - 6y = 12$ externally at the point $(1, -1)$, then the radius of $C$ is :
If one end of a focal chord of the parabola, $y^2 = 16x$ is at $(1, 4),$ then the length of this focal chord is
The complex that has highest crystal feild splitting energy $(\Delta )$, is :
The number of sigma ($\sigma$)and pi ($\pi$) bonds in pent-2-en-4-yne is :
The pair that does NOT require calcination is:
Hall-Heroult's process is given by :
$C_{60}$, an allotrope of carbon contains :
Iodine reacts with concentrated ${HNO_3}$ to yield $Y$ along with other products. The oxidation state of iodine in $Y$, is :
NaH is an example of :
The compound that inhibits the growth of tumors is :
The correct structure of tribromooctaoxide is
Two similar thin $equi-convex$ lenses, of focal length $f$ each, are kept coaxially in contact with each other such that the focal length of the combination is $F_1$. When the space between the two lenses is filled with glycerin (which has the same refractive index $(p = 1.5)$ as that of glass) then the equivalent focal length is $F_2$. The ratio $F_1$ : $F_2$ will be :
Two very long, straight, and insulated wires are kept at $90^{\circ}$ angle from each other in $xy$ - plane as shown in the figure. These wires carry currents of equal magnitude $I$, whose directions are shown in the figure. The net magnetic field at point $P$ will be :
A thermometer graduated according to a linear scale reads a value $x_0$ when in contact with boiling water, and $x_0/3$ when in contact with ice. What is the temperature of an object in $0 {^{\circ}C}$, if this thermometer in the contact with the object reads $x_0/2$ ?
A soap bubble, blown by a mechanical pump at the mough of a tube, increases in volume, with time, at a constant rate. The graph that correctly depicts the time dependence of pressure inside the bubble is given by :
How does steroid hormone influence the cellular activities?
Which of the following alkyl halides is used as a methylating agent ?
Surface tension of lyophillic sols is
When \(1M\ H_2SO_4\) is completely neutralised by sodium hydroxide, the heat liberated is 114.64 kJ. What is the enthalpy of neutralisation ?
Which of the following halides undergoes \(S_N1\) reaction at the fastest rate?
How many moles of \(KI\) are required to produce 0.4 moles of \(K_2HgI_4\)?
What is DDT among the following?